Thread protector



June 26, 1928, 1,674,998

F. J. SPANG THREAD PROTECTOR Filed Aug. 18, 1924 FIEl- III/[111W Patented dune 26,, N28.

entrain snares FERDINAND F. QFANG, @F BUTLER, PENNSYFVANM.

THREAD EJED'EEGTUE.

Application tiled August it, was. Serial No. raaaae.

This invention relates to thread rotectors such as are used to protect the t o of various implements and articles when in transit or while not in use.

lit is now considered good practice to use protectors for covering the threads of various articlesv such as tools for use in well drilling, pipes, stems and joints, etc. and an object of this invention is to produce an improved form of protecting device capable of being incorporated in both male and female protectors and especially those adapted for the boxes and pins of well drilling tools.

These boxes-so called-are threaded conim cal chambers formed in the ends of the joint members and the pins-so called-are threaded conical projections on such members. The pins and boxes are adapted to cooperate in securing tool elements together.

It is desirable to prevent moisture from gaining access to the threads and it is also desirable to be able to coat them with oilor grease and hold the same in place.

Another object of this invention is to pro- 25 duce both male and female protectors for the threaded boxes and pins'of well drilling tools or tool joints that will not only protect the threads thereof, but will keep moisture out and hold oil or grease in place thereon.

A further object is to produce protectors for the pins and boxes of well drllling tool elements or joints of material that is still enough to serve as a real protection yet is so 'much softer than the metal of which the 3 joints are formed that collision of the protectors with external objects will not in any manner injure the protected threads.

'lhese, as well as other objects which will be apparent to those skilled in the art to a which this invention relates, ll attain by means of the devices described in the specification and illustrated in the drawings accompanying and forming part of this application.

in the drawings- Figure 1 is a side elevation of a tool having a threaded pin, showing in section one embodiment of this invention applied thereto, Fig. 2 is a side elevation of the formof to this invention shown in F ig. 1, Fig.3 is

an end elevation and Fig. 4 is a longitudinal section thereof, Fig. 5 is a view of a tool provided with a box 'oint shg in section another to ct t is invention applied as theretc, ig. 6 is a section at the device wel shown in Fig. 5 and Fig. 7 is an end elevation thereof.

Figs. 1 tot illustrate an embodiment of this invention which is particularly adapted for use with a threaded pin, rod or the like such as the pin 10 of a well drilling tool ll. This form includes an annular body portion 112 made of flexible or elastic material such as rubber and which, in the present instant, is tapered throughout its length to conform to the tapered pin 10. The narrow end of the body 12 is provided with several threads 13 adapted to engage the threads at the outer end of the pin. Ridges 14 are formed on the outer face of the annular body 12 so as to provide a gripping surface for use in threading the protector on and 0d the pin 10. The other end of the annular member is provided with a flange 15 which has a slightly dished or concaved face 16, see Fig. 4, so that when the protector is in position on the pin 10, as shown in Fig. 1, the flange 15 will be slightly bent or flexed by contact with the shoulder 17 at the base of the pin 10 when the protector is applied so as to form an air tight joint between the thread protector and the shoulder 17. A chamber 18 is provided between the threads 13 and the flange 15 which may conveniently be filled with ase to prevent corrosion of the threads. 4

In Figs. 5 to 'i' there is shown another embodiment of the invention which is particularl adapted to protect the box 200i a 1 drilling tool 21. This form includes an annular member 22 having external threads 23 at one end for engaging the internal threads of the box 20. The other end is provided with a flange 24 which is formed similarly to the flange 15 so as to have an inclined bottom face 25. Ribs 26 are preferably formed within the annular member for use in threading and unthreading and the inner end of the threaded portion is closed by wall 26 with which the ribs 26 connect. en the member is threaded into the box the face of the flange 24 engages the end 27 of the tool and when the protector is in applied position, flange 24 is I flexed and thus caused to form an airtight W5 joint with end 27 of the tool.

'lhe protector is preferably made from rubber or rubber composition which will not itself injure the threads to which it may be applied and is suficiently flexible and elastic 1w to insure a tight joint between the deflected flange and the article at one end and between the threads of the protector and the threads of the article at the other end.

While I have described specific forms of this invention ll do not wish to be limited to the details thereof but what it claim as new and desire to secure by Letters Patent is:

1. A thread protector comprising a tapered hollow body open at both ends, a resilient internally threaded portion disposed adjacent the smaller end of said body and an outwardly extending dished resilient flange disposed on the larger end, the body of the said protector having an internal diameter greater than the internal diameter of the said threads.

2. The combination with a ta ered thread ed annular member having a shank portion at its larger end, of a thread protector comprising a hollow tapered cylindrical body open at both ends and having a resilient internally threaded portion at the smaller end of said body, the internal diameter of the said resilient threads being substantially the same as the external diameter of the aaraaae smaller end of the tapered threaded member, and a dished resilient flange disposed on the larger end of the body and extending outwardly therefrom, the internal diameter of the larger end of the thread protector being substantially the same as the external diameter of the shank portion on the threaded member, the main body portion of the thread protector having internal diameters greater than the corresponding external diameters of the said threaded annular member.

3. A thread protector including a body portion having a thread-engaging section located adjacent one end thereof, and an outwardly-extending annular flange of substantially greater diameter than said body portion and provided with an annular article-v engaging face positioned at an oblique angle to the axis of the protector and locatedat the other endw' In testimony whereof, l have hereunto subscribed my name this 12th day of August, 1924.

FERDINAND J. SPANG. 

